Pop-Up position compared to the marker clicked in OpenLayers

Question

I would like to center a pop-up on the marker where I click now it is moved to the right and above the marker.

I tried two methods:

Method 1:

var f = map.forEachFeatureAtPixel(
         event.pixel,
         function(ft, layer){return ft;}
  );
                                                    
  var geometry = f.getGeometry();
  var coord = geometry.getCoordinates();
                                                    
  content.innerHTML = featureStr;
  overlay.setPosition(coord);

Method 2:

content.innerHTML = featureStr;                                               
overlay.setPosition(getCenterOfExtent(extent));

function getCenterOfExtent(Extent){
       var X = Extent[0] + (Extent[2]-Extent[0])/2;
       var Y = Extent[1] + (Extent[3]-Extent[1])/2;
        return [X, Y];
}

In both cases, the pop-up does not move.

Any other ideas?